Container lift frame



March 10, 1970 ,FQRRY ETAL 3,499,563

CONTAINER LIFT FRAME Filed Dec. 21, 1967 I .4 Sheets-Sheet l INVENTORS JAMES E. FORRY CYRIL. J- NISBETT NORMAN D. THOMPSON 6 l i 3F; Z 77 :ITORNEYS March 10, 19 70 ,3, E FORRY ET AL 3,499,563

CONTAINER LIFT FRAME Filed Dec. 21, 1967 4 Sheets-Sheet z INVENTORS JAMES E. FORRY CYRIL. J. NISBETT NORMAN D. THOMPSON 1 I I W 7 ATZORNEYS' March 10,1970. J. E. FORRY ET 7 CONTAINER LIFT FRAME 4 Sheets-Sheet 3 Filed Dec. 21, 1967 INVENTORS JAMES E. FORRY CYRIL. J. NISBETT NORMAN D. THOMPSON ATTORNEYS J. E. FORRY ETAL "3,499,563 CONTAINER LIFT FRAME March 10, 1970 4 Sheets-Sheet 4 Filed Dec. 21, 1957 INVENTORS JAMES E. FORRY' CYRIL J. NISBETT NORMAN D THOMPSON pg. lat-a.

ATTORNEYS United States Patent U.S. Cl. 214-621 9 Claims ABSTRACT OF THE DISCLOSURE A frame for lifting and moving large transportation containers is provided. The lift frame is adapted for easy attachment and detachment to large size fork trucks. A vertical frame is provided for attachment to the lift carriage on a mast of a fork lift truck. Transversely extending arms form an extension on the upper corners of the frame. These transverse supporting arms pivotally support transverse clamping beams, which beams are provided with container lastching means at the extremities thereof. When properly positioned the lift frame of the invention engages the upper corner fittings of a cargo container whereby said container may be lifted and moved by said truck.

CROSS-REFERENCE TO RELATED APPLICATION The present invention describes a container lift frame which is related in purpose and operation to the lift frames disclosed and described in copending application Ser. No. 675,635, filed Oct. 16, 1967 for Anti-Racking Container Lift Frame by Theodore H. Allegri, Robert G. Neer and Norman D. Thompson.

BACKGROUND OF THE INVENTION The present invention relates to lift frames for cargo containers and more specifically to lift frames suitable for attaching to a fork lift truck.

Large fully enclosed cargo containers in lengths of twenty to thirty, and even forty feet, have been finding increasing favor with the transportation industry. Such containers constructed completely of metal, metal and wood or of metal and fiberglass form cargo units susceptible to eflicient cargo handling in that they may be rather easily transferred from truck to train and from train to ship and vice versa. Such containers also protect the cargo from theft and also present units which may be stacked and stored in outdoors locations while fully protecting the cargo therein from weather. Thus requirement for warehouse space is reduced during transshipment.

Further, although the cargo containers are of relatively large size, their regular shape and unifom size eases the problem of calculating correct cargo space for a given amount of cargo. Also the fully enclosed containers when lashed down on flatbed trailers or rail cars, may be readily transported from place to place.

Due to their standard size, i.e., nominally 8 ft. by 8 ft. by multiples of 10 ft., for instance 10, 20, 30 and 40 ft., such containers have been found to be extremely valuable for cargo shipments necessitating transportation by different means during their journey from shipping point to destination. Thus, in any one trip, a cargo container might travel first by truck, then by rail and then by truck to its ultimate destination. Or, for instanw, it might travel by truck, by ship and thence by rail to its final destination. It will be realized that when shipment involves passage on various types of transporting means, transfer and transshipment of the containers is necessitated.

3,499,563 Patented Mar. 10, 1970 "ice The transfer of such cargo containers from one means of transportation to another obviously necessitates the unloading of the containers from one means of transportation, then transporting and reloading of the container on another means of transportation. The transshipment of the cargo containers obviously requires some means of movement. Since the containers when loaded with cargo may reach weights up to 50,000 pounds in the case of 20 ft. containers, and even up to 75,000 pounds in the case of 40 ft. containers, it will be realized that the transshipment thereof presents quite a problem. Prior art devices for lifting and loading such cargo containers includes cranes and derricks of various forms, straddle lift carriers and lift trucks of one sort or another.

Most prior art devices, whether working from a crane, straddle carrier or truck, utilize a generally rectangular frame having side dimensions equal to the top dimensions of the cargo container, which frame incorporates standardized twist lock fittings (such as discussed in greater detail hereinafter) depending from each corner thereof. The frame and associated twist locks is generally suspended from some overhead device by means of cable or chain to lift the cargo containers.

As stated before, the dimensions of such cargo containers have been standardized. In addition the corner fittings on such containers have also been standardized whereby hooks and shackles of specified dimensions will suitably engage said containers. A twist lock of a safety type has been designed and standardized for use on the corner fittings of such containers. The standard corner fittings, twist lock latching means and the container dimensions are set forth in a publication of the United States of America Standards Institute. The Institute is located at 10 E. 40th Street, New York. The publication is entitled Specifications for Freight Containers, and is designated MH 5.l-1-962. The publication may be secured from the above noted organization, which publication completely describes the standardized cargo containers, standardized corner fittings, and the standardized twist lock latch means for use therewith.

In any event, prior art cargo container lifting devices have proven to be rather cumbersome and inefiicient. For instance the crane devices suffer from the defect that they are restricted in their area of operation, since they work either from fixed towers or on rails. The straddle carrier type of container lift devices, while having more freedom of movement than the crane devices, must strad die the cargo container completely before it can lift and move it.

To date the most eflicient means for loading and unloading cargo containers resides in the use of wheeled lift trucks adapted to move up to the sideof a cargo container which is then lifted and transported utilizing the mast common to such vehicles. Cargo'container transshipment by means of lift trucks is potentially the most eflicient in point of time and in freedom of movement of all prior art devices utilized for such purposes.

The principal drawback in the use of lift trucks for transshipment of cargo containers resides in the fact that the lift truck must operate from one side of the cargo container. If the lift truck utilizes the four corners of the cargo container facing it along one vertical side, the problems of twisting and racking of the cargo container become of great concern. It will be appreciated that if the cargo container is picked up from one side thereof, the great weights involved, as noted above, place great loading forces upon the cargo container frame whereby severe twisting and racking thereof may occur. In overhead type of lift devices, i.e., cranes and straddle carriers, the upper four corners of the cargo container are generally utilized as the lift point whereby the entire container is suspended directly below the lift mechanism.

Racking and twisting problems are therefore greatly reduced by these transshipping devices.

SUMMARY OF THE INVENTION The present invention provides a lift frame for cargo containers which is adapted for use on fork lift trucks, but in addition provides the advantages of overhead suspension discussed above. The lift frame of the present invention, when fitted to a fork lift truck, lifts the cargo container at the four upper corners thereof. By lifting, supporting and stabilizing the cargo container at the noted four positions, the entire weight of the container is suspended directly from the overhead portion of the lift frame whereby any racking and twisting thereof is virtually eliminated. In addition, since the frame is adapted for use on a fork lift vehicle, the cargo container may be lifted and carried from place to place in the shortest possible time and in the most efiicient manner.

It is therefore an object of the invention to provide a device whereby cargo containers may be lifted and transported by fork lift truck means.

It is a further object of the invention to provide a container lift frame that supports the cargo container from the upper four corners thereof while thereby permitting lifting and transporting of a cargo container by a fork lift truck.

It is yet another object of the invention to provide a container lift frame that reduces racking and twisting of the cargo container.

It is still another object of the invention to provide a cargo container lift frame that may be quickly and simply placed on or removed from a standard fork lift vehicle.

It is still another object of the invention to provide a cargo container lift frame including the advantages of lifting the cargo container from the top four corners in the manner of a crane or straddle device, but also including the ease and efliciency of fork lift vehicle transportation.

Further objects and advantages of the invention will be apparent from a review of the following specification and claims along with the accompanying drawing which comprises:

FIG. 1, an isometric view of the container lift frame of the invention shown in position on a fork carriage (in phantom), mast (in phantom), and lift truck (in phantorn);

FIG. 2, an isometric view of one of the transverse arms with the lift beam pivoted thereto and also showing a portion of the vertical upright frame;

FIG. 3 is a plan view of the transverse arm and pivoted lift beam with portions cut away to show the locking rod and locking pin levers contained within the lift beam; and

FIG. 4, an isometric view of the lift frame of the invention in position on a lift truck and showing a container clamped thereon and raised off the ground.

DESCRIPTION OF THE INVENTION As is most clearly shown in FIG. 1 of the drawing, the lift frame 11 of the invention comprises a vertical frame portion 12 having two outwardly extending transverse arms 13 and 14 that comprise extensions to the upper corners of the vertical frame. The entire lift frame 11 is re movably mounted on the fork carriage 15 which is conventionally attached to the mast structure 16 mounted on a lift truck 17.

The vertical frame 12 is of a generally rectangular configuration and is fabricated from heavy steel box beams. Two box beams 18 and 19 form the upright outer members thereof, while similar beams 21 and 22 form the lower and upper cross members of the frame respectively. Inward of end beams 18 and 19 and placed sufficiently far apart to just straddle lift carriage 15, are two additio al verti al reinforcing beams 23 and 4 h h a welded at their respective ends to cross beams 21 and 22, as are the end beams 18 and 19.

Diagonal bracing members 26 and 27 are further welded to the lower corners of the frame 12 and to the junctions where vertical beams 23 and 24 meet upper cross beam 22.

Depending C-shaped brackets 28 and 29 are welded to the underside of upper cross beam 22, which brackets are adapted to fit over the upper cross beam of the common fork carriage 15. Pivoting keeper lugs 31 and 32 are bolted to the back side of vertical beams 23 and 24 at a point approximately midway between cross beams 21 and 22. Pivoted lugs 31 and 32 may be swiveled to the horizontal position (as shown in FIG. 1) whereby they fit behind the vertical side beams of fork carriage 15. The removable pins (not shown) pass through lugs 31 and 32 into vertical beams 23 and '24 to retain the lugs in the horizontal position. An additional two lugs 25 and 30 are welded to bottom beam 21 and extend upwardly in front of carriage 15, whereby the bottom portion of upright frame 12 is stabilized. Thus the entire lift frame 11 is securely mounted on the fork carriage 15 by means of brackets 28 and 29, keeper lugs 31 and 32, and lugs 25 and 30.

If it is desired to remove lift frame 11 from the lift truck, the pins are simply removed from lugs 31 and 32 whereby they may be swiveled into the vertical position in back of vertical beams 23 and 24. The entire lift frame 11 may then be easily removed from the fork carriage of lift truck 17 by suitably lowering carriage 15 to disengage brackets 28 and 29. Similarly lift frame 11 may be remounted on the fork lift carriage of lift truck 17 by simply engaging-the fork carriage 15 with brackets 28 and 29, and thereafter resecuring lugs 31 and 32 behind the vertical end beams of the fork lift carriage.

As noted previously, transverse arms 13 and 14 form an extension of the upper outer corners of vertical frame 12. These arms 13- and 14 extend horizontally outwardly away from lift truck -17 for a distance of somewhat more than half the width, i.e., four feet, of a standard cargo container. Depending from each transverse arm 13 and 14 and pivoted thereto, are transversely extending support and lift beams 33 and 34. Arm 14, and depending beam 34, is a mirror image of transverse arm 13 and its depending beam 33. Similarly, the apparatus which will be more fully described hereinafter, associated With each of the arms is identical in construction. For purposes of simplicity and construction of arms 13 and 14, beams 33 and 34 and their associated apparatus will be discussed in relation to arm 13 and beam 33 only. However it should be understood that the mechanism associated therewith and therein is identical with that associated with arm 14 and beam 34.

As is more clearly illustrated in FIG. 2, transverse arm 13 has two downwardly extending lugs (one of which is not shown) welded thereto a short distance inwardly of the outer end thereof. Support and lift beam 33 is pivoted to transverse arm 13 by a pin 36 that passes through the midpoint of support and lift beam 33 and is retained within bearing holes drilled into the lower portion of the depending lugs. Thus, support and lift beam 33 is free to rotate in the vertical plane about the point fixed by pin 36. However support and lift beam 33 is limited in its extent of rotation by resilient load stops 37 and 38 mounted on the underside of transverse arm 13, one on either side of the depending lugs.

It should be further noted that support and lift beam 33 cannot swing freely about the pivot point formed by pin 36, but is further restricted in its movement by a load swing damper 39 which is aflixed at one of its ends to brackets rigidly mounted on transverse arm 13- and at its other end to brackets rigidly mounted on support and lift beam 33. As illustrated in the drawing, load swing damper 39 takes the form of a conventional shock absorber me han m h e y i t n upport arm 33 i p mit ed to rotate about the pivot point, but wherein such rotation is controlled and damped by the shock absorber mechanism.

If morepositive control of the movement and position of support and lift beam 33 is desired, a conventional double acting hydraulic lack with associated hydraulic lines and control valves may be substituted for the simple shock absorber mechanism illustrated in the drawing. In such event the relative angle between support and lift beam 33 and transverse arm 13 can be positively controlled by the vehicle operator utilizing conventional hydraulic controls and mechanisms.

As most clearly illustrated in FIG. 2, a pair of standard twist locks 41 and 42 depend from support and lift beam 33, one at either end thereof. Details of construction of such twist locks (safety type) may be found in United States of America Standards Institute Document MH 5.1-1962 Specifications for Freight Containers previously referred to above.

These standardized twist locks 41 and 42 comprise a rotatable elliptical head portion 43 and 43' which is secured to a shaft 44 and 44' (see FIG. 3) which shaft passes through a fitting 46 and 46 into the interior of hollow beam 33. Fitting 46 and 46' is welded to the under portion of beam 33 and in turn retains the locking mechanism thereon. Within the interior of beam 33 an actuating lever 47 is rigidly secured to shaft 44. An actuating rod 48 is in turn pivotally secured to the other end of lever 47 and in turn passes along the entire interior length of beam 33 to the other end thereof at which point it is pivotally secured to an identical actuating lever 49 on corresponding shaft 44'. At a suitable point between the ends thereof rod 48 has a horizontal hole drilled therethrough. A pin 51 passes through said hole and horizontally out through a slot 52 formed in one side wall of beam 33. Slot 52 extends for some distance along the length of the side wall of beam 33 whereby pin 51 may be translated back or forth along the slot by means thereinafter described.

The end of pin 51 remote from rod 48 is fixedly retained in the end of hydraulic jack rod '53 which extends from hydraulic jack cylinder 54 that is in turn retained by suitable brackets on the side wall of beam 33. Hydraulic cylinder 54 and associated rod 53 together comprise a double-acting hydraulic jack 56, which is in turn supplied with hydraulic fluid through suitable hose connections (see FIG. 2) leading from the necessary control valves (not shown) at the vehicle operators station.

When desired the vehicle operator may direct hydraulic fluid to one end or the other of cylinder 54 whereby pin 51 is moved in one direction or the other along beam 33. Such movement in turn forces rod 48 to actuate the rotatable heads on twist locks 41 and 42. By such means the heads of twist locks 41 and 42 may be rotated either into the locked or unlocked position. When dropped through the slotted top opening of a standard corner fitting (the cargo container standardized corner fittings are shown and described in the above referred to USA. Standards Institute publication) of the cargo container and rotated 90 into the locking position, heads of twist locks 41 and 42 will be locked into such corner fittings of the cargo container. When rotated 90 back from the locking position, twist locks 41 and 42 may be removed through the slotted opening in the corner fittings of a standardized cargo container.

Since twist locks 41 and 42 are connected by actuating rod 48, it is apparent that both twist locks will be rotated either into the locking or unlocking position at the same time.

If desired, suitable mechanisms may be attached to beam 33 to indicate whether or not twist locks 41 and 42 are positioned within the corner fittings of a cargo container and also to indicate whether or not such twist locks are in the locked or unlocked positions. Suitable types of such mechanisms are described and shown in copending application Ser. No. 675,635 referred to above.

In operation, with the lift frame .11 secured to the lift carriage 15 as previously described, and with the twist looks at either end of the lift beams 33 and 34 in the unlocked position, the vehicle operator approaches a cargo container 58 along one of its long sides. It should be noted that upright frame 12 and associated transverse arms 13 and 14 is of a length equal to the length of the container '58 which is to be lifted and transported. Further, depending beams 33 and 34 are of a length equal to the width of container 58. The pair of twist locks associated with each lift beam 33 and 34 are set apart by a distance exactly equal to the distance between the upper corner fittings on either end of container 58.

Thus the operator approaches container 58 with frame 11 lifted high enough to provide clearance between the top of the container and the bottom of the twist locks depending from beams 33 and 34. The operator maneuvers the vehicle to a position alongside container 58 whereby the twist locks are brought to a position immediately above the corner fittings of the container 58.

When in a suitable position, the operator then lowers lift carriage 15 and the attached container lift frame 11 until the four twist lock heads are engaged within the upper four corner fittings of container 58. It shou d be noted that since beams 33 and 34 are pivoted on their respective transverse arms 13 and 14, each arm will be free to rotate if necessary in order to completely engage the twist lock heads within the upper corner fittings of container 58 even if the container has been twisted or racked out of the horizontal plane.

In any event, once the twist locks are engaged in the upper corner fittings of the container 58, the operator actuates hydraulic jacks 56 to lock the twist lock heads within the corner fittings. Once locked within the upper corner fittings of container 58, the operator then raises lift carriage 15 on mast 16 whereby the container 58 is lifted by its upper four corners. If desired, the operator may tilt mast 16 slightly backward in order to bring the side of container 58 to rest against the adjacent portions of upright frame 12.

Load swing dampers 39 also serve to snub any swinging tendency of the container. In the event positive control hydraulic jacks are utilized instead of dampers 39, the operator may visually align beams 33 and 34 with the top of the container and any warping of the container out of the horizontal plane is then accommodated for and the twist locks will suitably engage the container corner fittings.

In any event, lifting container '58 by its upper four corners, the operator may then trans-port it to any desired location. The container may be stacked on the top of other containers, it may be loaded on a truck bed for highway transportation, it may be loaded onto a rail flat car for railway transportation, or it may be deposited at dock side for hoisting onto a cargo vessel.

Once deposited in the desired position, the operator simply actuates hydraulic cylinder 56 to unlock the twist locks depending from lift beams 33 and 34. He then raises lift carriage 15 to disengage the locks from the top corner fittings of container 58. The lift vehicle 17 is then backed away from the container and driven to the next container for a succeeding sequence of operations.

Utilizing the lift frame 11 as described above, cargo containers may be quickly and efficiently picked up and moved from place to place even when fully loaded. The locking and unlocking operations are conducted in a minimum amount of time. Further, since the cargo container is supported and held at the upper four corner positions as indicated, additional racking or twisting of even fully loaded containers is virtually eliminated, since the entire weight of the container hangs directly below the lifting points.

While a preferred embodiment of the invention has been shown and described, those skilled in the art may make minor variations without departing from the spirit of the invention.

What is claimed is:

1. A cargo container lift frame comprising an upright frame, first and second outwardly extending arm-s rigidly secured to the upper portion of said upright frame, first and second lift beams pivoted to said first and second arms respectively and depending therefrom so that the beams may pivot independently of each other, container engaging means secured to said beams at positions for mating with corner fittings formed into the upper corners of said cargo container, and means for locking to and unlocking said engaging means from said container corner fittings.

2. The lift frame of claim 1 wherein said first and second lift beams are pivoted to the first and second arms by pins having their axis in a horizontal plane whereby each said beam is free to move relative to the other beam and in a vertical plane.

3. A cargo container lift frame comprising an upright frame, first and second outwardly extending arms rigidly secured to the upper portion of said upright frame, first and second lift beams pivoted to said first and second arms respectively, by pins having their axis in a horizontal plane whereby each said beam moves relative to the other beam and in a vertical plane, container engaging means secured to said beams at positions for mating with corner fittings formed into the upper corners of said cargo container, means for looking to and unlocking said engaging means from said container corner fittings, and damper means connected between said beams and said arms respectively to control the freedom of moveis restricted by resilient stops affixed to and depending from said arms.

7. The container lift frame of claim 1 wherein bracket means and lug means are affixed to said upright frame for attaching said lift frame to the fork carriage of a fork lift truck.

8. The container lift frame of claim 1 wherein said means for locking and unlocking the container engaging means comprises hydraulic jack means mounted on said first and second beams respectively.

9. The container lift frame of claim 2 wherein said arms extend away from said upright frame for a distance at least one-half the width of a standard cargo container, said lift beams are of a length at least equal to the full width of a standard cargo container and wherein said lift beams are pivoted at their approximate midpoints to said arms.

References Cited UNITED STATES PATENTS 2,547,502 4/ 1951 Smith et a1. 2,578,802 12/1951 Heidrick et al. 214-654 X 2,653,725 9/1953 Dodge 214-651 2,807,493 9/1957 Ryan et al. 3,045,852 7/1962 Boyd 214-653 3,057,490 10/1962 Sauer 214-77 3,124,263 3/1964 Eaves 214-654 3,146,903 9/1964 Bjorklund 214-394 3,176,866 4/ 1965 Meister 214-620 FOREIGN PATENTS 1,220,063 1/ 1960 France. 1,379,957 10/ 1964 France.

868,814 5/1961 Great Britain.

ROBERT G. SHERIDAN, Primary Examiner ROBERT J. SPAR, Assistant Examiner US. Cl. X.R. 294-67, 81 

